Climate suitability division of solar greenhouse in Inner Mongolia Autonomous Region, China.

To resolve the issue of scientific planning and rational layout of different vegetable greenhouses in Inner Mongolia Autonomous Region, we selected the days of low temperature in winter, sunshine hours, overcast days, extreme minimum temperature, days of monsoon disaster, days of snow cover in production season of greenhouse as the climate zoning indicators, based on ground-based observation data from 119 meteorological stations (1991 to 2020) and the growing demand of leafy and fruity vegetables in greenhouse, combined with the analysis of key meteorological factors in production season and the study of meteorological disaster indicators such as low temperature and cold damage, wind disaster, snow disaster. We analyzed the indices, classification and division of comprehensive climate suitability zoning of leafy and fruity vegetables at various slopes (35°, 40°) of solar greenhouse by the weighted sum method. The results showed that the climatic suitability zoning grades of leafy and fruity vegetables at 35° and 40° slope of greenhouse was highly consistent, and that the greenhouse climate suitability of leafy vegetables was higher than that of fruity vegetables in the same region. As the slope increased, wind disaster index decreased and snow disaster index increased. Climate suitability was different in areas affected by wind and snow disasters. The northeast of the study area was mainly affected by snow disasters, and the climate suitability of 40° slope was higher than 35°. The southeast of the study area was mainly affected by wind disasters, and the climate suitability of 35° slope was higher than 40°. Alxa League, Hetao Irrigation District, Tumochuan Plain, most parts of Ordos, southeast of Yanshan foothills and the south of West Liaohe Plain were the most suitable area for the solar greenhouse, because they had the suitable solar and hot resources and the low risks of wind and snow damage, which were also the key development areas of current and future facility agriculture. Due to the deficiency of solar and hot resources, high energy consumption in greenhouse production and frequent snow storms, the area around Khingan range in the northeast of Inner Mongolia was unsuitable for greenhouse.

[Light and temperature indices during the seeding stage of spring maize in Hetao irrigation district, Inner Mongolia, China].

We collected the experimental dataset of a spring-maize in Hetao irrigation district (Bayannaoer, Inner Mongolia) during 2012 and 2013, as well as the crop data observed in related agrometeorological stations to investigate the impacts of light and temperature variation on maize development during the seedling stage to derive adequate light and temperature indices for different suitability. Furthermore, polynomial fitting was applied to interpolate the temperature indices for each day of the whole seedling period to draw the dynamics of the temperature indices and to better characterize its influence on maize development during the seedling stage. The results suggested that the emergence and development rates increased by 11% and 12%, respectively when the average temperature increased 1 °C during the sowing-emergence period and emergence-jointing period, and the biological lowest temperature was 7.4 and 11.9°C , respectively. The optimum temperature at the sowing-emergence stage ranged from 16.0 to 18.0°C , and the leaf area index at the three-leaf stage reached 0.0172 and above. The optimum temperature at the emergence-jointing stage ranged from 21.6 to 23.0°0C , and the photosynthesis/growth of plant tissue was positively correlated with the temperature. The leaf area index in the jointing period could reach 2.15 and the plant height was 120 cm. At the emergence-jointing stage, when the sunshine percentage 74%, or the daily sunshine hours ≥11.0 h . d-1 , or the total sunshine hours ≥540 h, the dry mass of plant tissue could